[BUGS-5623] Set missing_redis_message if Redis service is not connect…

…ed (#391)

* Set missing_redis_message if Redis is not connected

* i18n

wp-redis.php

@@ -53,10 +53,14 @@ function wp_redis_get_info() {
 	}
 
 	if ( ! defined( 'WP_REDIS_OBJECT_CACHE' ) || ! WP_REDIS_OBJECT_CACHE ) {
-		return new WP_Error( 'wp-redis', 'WP Redis object-cache.php file is missing from the wp-content/ directory.' );
+		return new WP_Error( 'wp-redis', __( 'WP Redis object-cache.php file is missing from the wp-content/ directory.', 'wp-redis' ) );
 	}
 
 	if ( ! $wp_object_cache->is_redis_connected ) {
+		if ( ! isset( $wp_object_cache->missing_redis_message ) ) {
+			$wp_object_cache->missing_redis_message = __( 'A Redis service needs to be enabled before the WP Redis object cache will function properly.', 'wp-redis' );
+		}
+
 		return new WP_Error( 'wp-redis', $wp_object_cache->missing_redis_message );
 	}